在大量气候变化模拟中量化建模不确定性
James M Murphy1, David M H Sexton, David N Barnett
1Hadley Centre for Climate Prediction and Research, Met Office, FitzRoy Road, Exeter EX1 3PB, UK. james.murphy@metoffice.com
Nature
|August 13, 2004
概括
这项研究使用大量气候模型量化了气候变化的不确定性. 它为全球气温上升的可靠概率范围提供了可靠的概率范围,因为二氧化碳的增加是两倍的.
科学领域:
- 气候科学 气候科学
- 地球系统科学 地球系统科学
- 环境建模环境建模
背景情况:
- 全球气候模型对于预测未来的气候变化至关重要.
- 模型参数中的不确定性导致了广泛的预测.
- 评估不同气候模型的相对质量是一项挑战.
研究的目的:
- 系统地确定符合模型不确定性的气候变化范围.
- 为了估计气候对二氧化碳增加一倍的敏感度的概率密度函数.
- 提供更可靠的区域气候变化预测范围.
主要方法:
- 根据不同的参数构建一个由53个成员组成的气候模型版本组合.
- 对气候敏感性的概率密度函数的估计.
- 用客观可靠性估计和专家建议限制概率密度函数.
主要成果:
- 对气候对大气二氧化碳增加一倍的敏感度的5-95%的概率范围估计为2.4-5.4摄氏度.
- 整体方法比传统方法产生了更广泛的区域气候变化.
- 客观可靠性估计提高了对模型不确定性的评估.
结论:
- 这种系统的方法减少了气候变化预测中的不确定性.
- 这些发现为气候变化适应和减缓规划提供了更强大的基础.
- 用各种参数进行集体建模,为评估气候变化影响提供了一种卓越的方法.
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